(This is just a quick history to set the scene, and frankly a bit boring. We won't be offended if you skip straight to the next section!)
The design of the QRP2001 has evolved over a long period of time: the design presented here represents several years of intermittent thinking, prototyping, objective evaluation, drinking of beer and eating of apple cake (although not at the same time).
The story starts back in 1998 when we first began work on the QRP2000 project: this culminated in a number of magazine articles and a presentation at the FDIM QRP convention at Dayton in May 1999. Although the idea generated quite a lot of interest, it was not sufficient to justify designing and making PCB's.
The QRP2000 prototype was scratch-built and we expected that a QRP kit supplier would be interested in having the PCB's done. What has become apparent to us is how small the QRP market is. QRP suppliers can only provide this type of commitment if the design would be marketed as a "foolproof" kit, which then needs to be published in one of the major US, UK or German Ham Radio Magazines. We did not have the time for this.
The original design for the QRP2000 can still be found elsewhere on the internet.
The QRP2000 was based on the excellent R2/T2 designs from KK7B (see Credits), and offered a high level of performance...but it suffered from a number of disadvantages. The main problem was that it required two AD9850 synthesizer chips, and that was making the cost of any kit very expensive (especially now that the AD9850 is on allocation and the UK price for small quantities has doubled to £35.- each). The design also lacked a number of features which we considered useful - most notably AGC circuitry.
Steve Farthing (G0XAR) and Jan Verduyn (G0BBL) were the brains behind the original QRP2000 design, and became convinced that we could develop a better, cheaper receiver design. Jan began work on the QRP2001 immediately after the Dayton convention, and the first prototype of the new design was demonstrated at Rochdale QRP Convention in November 1999. Technical details were also published in Sprat magazine, Winter 1999/2000 edition.
Since then the design has been further refined, and an updated version was again presented at Rochdale QRP Convention in 2001.
This is the design (with a few minor updates) which appears here: we hope you like it!